Tokyo
London
Convert JST to GMT
Japan Standard Time to Greenwich Mean Time — London is 8 hours behind Tokyo
Quick Facts
Time Difference
-8 hours
JST Full Name
Japan Standard Time
GMT Full Name
Greenwich Mean Time
JST to GMT Conversion Table
Related Conversions
About JST and GMT Time Zones
JST (Japan Standard Time) is UTC+9 and covers cities like Tokyo, Osaka, Kyoto. GMT (Greenwich Mean Time) is UTC+0 and covers cities like London, Dublin, Lisbon.
When it's 12:00 PM (noon) in Tokyo (JST), it's 4:00 AM in London (GMT). The time difference between JST and GMT is 8 hours — London is behind Tokyo.
The 9-hour difference makes real-time overlap challenging — early morning calls (7–9 AM JST) work best.
Use our world clock tool to compare Tokyo and London with a visual timeline, or browse more timezone conversions.
Frequently Asked Questions
What is the time difference between JST and GMT?
London (GMT) is 8 hours behind Tokyo (JST). The offset is -8 hours.
Is GMT ahead or behind JST?
GMT is 8 hours behind JST. JST is UTC+9 and GMT is UTC+1.
When it's 12:00 PM in Tokyo, what time is it in London?
When it's 12:00 PM (noon) in Tokyo (JST), it's 4:00 AM in London (GMT).
When it's 5:00 PM in Tokyo, what time is it in London?
When it's 5:00 PM in Tokyo (JST), it's 9:00 AM in London (GMT).